1. Field of the Invention
The present invention concerns a fitting for transverse joining of two L-shaped sections, each with a web part and a foot part, where the sections are disposed back-to-back, e.g. scaffold boards.
2. Description of Prior Art
Scaffold boards of the type with a board face provided with downwards extending L-shaped sections at both long sides so as to constitute a substantially C-shaped cross-section in the assembled state are prior art. Such a scaffold board is shown in FIGS. 1A-1C.
Such scaffold boards typically have a width of about 30 cm, and therefore it is common to dispose several boards side by side in order to achieve a wider surface to walk on. If the load on a board is greater than the load on the adjacent board, the first-mentioned board will be deflected more than the other, whereby an edge or a step appears, which is undesirable. Besides, it is generally desirable to assemble several boards together in a mechanical way in order thereby to enhance the load capacity of the boards by transferring forces from one board to the adjacent boards.
Means for assembling such boards exist. For example, it is prior art to provide the boards with pieces of flat bar welded on and with a hole for bolting together with a top fitting. This method has a number of drawbacks. Firstly, special tools are to be used for this assembling method, which is inexpedient, as the tool is sometimes to be transported to great heights and used under difficult weather conditions. Secondly, several components are to be used for the bolting, which is inexpedient as it requires considerable capacity for storage and logistics on the part of the scaffold firms. A third drawback is that this method implies very little freedom for mutual disposition of the boards as the boards only can be assembled so that the flat bar pieces overlap. Furthermore, this prior art assembling method has the drawback that it takes up space 8-15 mm in vertical direction, increasing the possibility of accidents where the workmen on the scaffold hit their heads on the joints.
Furthermore, there is a prior art solution where the boards are provided with holes in the side members of the boards which are then to be assembled with bolts, nuts and washers. This method also has a number of drawbacks. Firstly, in this case special tools are to be used for this assembling method, which is inexpedient as it is sometimes to be lifted to great heights and to be used under difficult weather conditions. Secondly, more components are to be used for the bolting together, which is inexpedient as it requires considerable capacity for storage and logistics on the part of the scaffolding firms. A third drawback is that bolts, washers and nuts are in danger of falling down from great heights since it can be difficult to assemble the relatively numerous components.